Python实现凯撒密码（加解密）

对输入字符进行编码

思路：利用字符对应的ASCII 码，进行移位，实现加解码

# 编码
def encode(x):
    for i in x:
        if i.isspace():
            print(' ', end='')
            continue
        new_c = ord(i) - 29

        if new_c > 90:
            new_c -= 26
        print(f'{chr(new_c)}', end='')

解码

# 解码
def decode(x):
    for i in x:
        if i.isspace():
            print(' ', end='')
            continue
        new_c = ord(i) + 29

        if new_c < 97:
            new_c += 26
        print(f'{chr(new_c)}', end='')

主程序入口

c = input('输入明文：')

if c.islower():
    print('加密后为: ', end='')
    encode(c)
elif c.isupper():
    print('解密后为：',end='')
    decode(c)
else:
    print('输入错误！')

实现效果

D:\腾讯手游助手\python\python.exe D:/project/cryptography/Crypt.py
输入明文：omnia gallia est divasa in partes  tres
加密后为: RPQLD JDOOLD HVW GLYDVD LQ SDUWHV  WUHV
Process finished with exit code 0

输入明文：RPQLD JDOOLD HVW GLYDVD LQ SDUWHV  WUHV
解密后为：omnia gallia est divasa in partes  tres
Process finished with exit code 0